WASHINGTON – Lobbyists are seeking ways to exploit new loopholes in campaign-finance reform as the Senate moved closer to the first overhaul of the rules since the Watergate era.

The final vote was put off until Monday because several senators last night wanted to go to a radio and TV correspondents dinner and others (some with wives) went to Alaska for the weekend to inspect caribou at a site where President Bush wants to drill for natural gas.

Senate supporters of revamping campaign-finance laws showed they have enough votes to pass a bill to ban unregulated, unlimited “soft money” contributions to political parties.

An amendment that would keep the essence of the bill alive even if the courts strike down part of it passed 57-43 after reformer-in-chief John McCain (R-Ariz.) said it was vital.

But lobbyists and watchdog groups predicted any ban on soft money will lead to a flourishing of politically oriented groups not required to disclose their spending.

“These people are already plotting,” said Sen. Robert Bennett (R-Utah). “If an individual is corrupt, he’s going to stay corrupt. . . . He’s going to find a way to game the system to his advantage.”

A D.C. lobbyist agreed: “The money will always flow . . . This bill weakens the party system, so there will be a fertile environment for creating front groups for everything.”

Steve Weiss of the Center for Responsive Politics said he expects a big increase in politically oriented nonprofit groups – modeled after the National Rifle Association and the Sierra Club – that could keep their donor lists a secret.

A soft-money ban could cost the parties millions in cash to spend on TV ads promoting their candidates – but independent groups would likely take their place.

“They do it now, but the reason why they don’t do as much of it is because there is soft money that you can give directly to the party – and why not impress the beneficiary of your contribution by giving it directly to them?” Weiss said.

But the Senate did increase the amount of regulated “hard money” that donors can give, from $1,000 to $2,000 per race, or a total of $4,000 for the primary and general election.

As a result, watchdogs expect more members of Congress to start new “leadership” political action committees – in addition to their personal campaign committees – that can each raise the maximum in hard money.

Democrats predict they’ll be hurt most by the reforms because they’re more dependent on “soft money.” House Democratic leaders may try to modify the bill.

Bush says he wants to sign a reform bill.

Last night, the Senate passed, by voice vote, an amendment co-sponsored by Sen. Hillary Clinton to make sure the new law won’t stop political parties from spending soft money on voter-registration drives.

NOT PRACTICING WHAT THEY PREACH

What they say isn’t always the same as what they do — key lawmakers have been eagerly raising the kind of unregulated ‘soft money’ that the McCain-Feingold reform bill would ban:

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* Sen. Hillary Clinton (D-N.Y.), who backs McCain’s bill, was the single biggest raiser of soft money for Senate Democrats last year through her New York Senate 2000 committee — it raised $9.7 million, according to Common Cause.

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* Senate and House Republicans raised $7 million, much of it soft money, Thursday night at a dinner with Vice President Dick Cheney as guest of honor. Republicans say this isn’t hypocritical since their party hasn’t taken a stand against soft money — while the Democratic party has.

* President Bush — who has said he hopes to sign a reform bill this year — will be the guest of honor at a June 27 GOP soft-money extravaganza that aims to raise at least $10 million.

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* The House Democratic Congressional Campaign Committee, headed by Rep. Nita Lowey (D-Westchester), recently boasted it has a record $6 million in cash on hand — $3 million in soft money.

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* The Democratic National Committee — led by Terry McAuliffe, the party’s top raiser of soft money, and famed for his role in Clinton White House sleepovers — is calling for a ban on soft money. But as of the end of 2000, it had $7 million cash on hand, including $2.3 million in soft money.

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* Three pro-reform Democratic senators up for re-election next year have filed papers within the past five weeks to let them raise soft money — Sens. Max Baucus (Mt.), Max Cleland (Ga.) and Dick Durbin (Ill.).

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* Critics blasted chief reformer Sen. John McCain (R-Ariz.) over a soft-money group’s TV ads promoting the reform bill in the final days before the vote. McCain — who let the group, Americans for Reform, use a Senate hearing room, said its actions would still be legal under his bill.